1. Field of the Invention
This invention relates to a communication system for dynamically modifying a queue of documents arranged for transmission. In particular, it pertains to a communication system to provide an operator with the capability of accessing entries in the send queue which have not been transmitted. The system allows the operator to alter, revise or otherwise change the transmission sequence of these entries prior to the transmission as a foreground systems task while the background system transmission or reception of the documents continues.
2. Description of the Prior Art
Electronic digital signal processing systems have been developed as operator controlled word and data processing machines. Word/data processing machines have also been provided with communication systems wherein one signal processing system is transmitting documents to one or more other signal processing systems. In communication systems for word processing systems, a word processing display terminal may transmit documents to one or more data receiving terminals which also may be word processing terminals. In such communication systems, it is well known to arrange the documents to be transmitted in a sequential queue, also known as the send queue.
Operator intervention may be required following the start of the transmission of documents in the send queue to the data receiving terminal. For example, the operator may desire to add a document to the send queue, delete a document previously placed in the send queue, or revise the send queue because of a detected error. In present word processing communication systems, the entire transmission must be interrupted in order to alter entries in the send queue. Present communication systems do not have the capability of altering the entries in the send queue dynamically while the background transmission or reception of documents continues.
The absolute separation between the communication task setup and its execution was a limitation of prior communication systems. In such prior communication systems, the send queue had to be completely and correctly specified off line prior to the commencement of transmitting documents. If a new document had to be entered to the send queue or if changes were required in any of the options associated with a queue entry, all communication activity had to be terminated while the change was made and session activity then restarted.
In addition, in present communication systems the situation may arise where the sending operator desires to "backup" and resend one or more jobs which have previously been sent during a session activity. As one example of this, the data receiving terminal may have had a temporary diskette problem which has been corrected. The operator may desire transmission to resume at the start of the aborted job. The sending operator may also have incorrectly specified a send document option (e.g., wrong data stream type) which has been noted and corrected and now the operator wishes to resend the job. In some communication systems where the sequence of the documents is not critical, one way to accomplish these corrections is simply to requeue the send document at the end of the queue and delete the earlier entry. However, this approach which may be taken with present communication systems cannot be used when the sequence of the documents is critical. In this situation, the operator must resend the sequence of jobs from the beginning.
A need has thus arisen for an improved communications system for word/data processing systems which enables the operator to dynamically alter the send queue to revise, remove or substitute documents without interrupting the transmission session. A need has also arisen for operator capability in a communication system to cause a sending sequence to be changed to any point in the queue without affecting the ordering of the queue.